Pokeit Pre-Flop Prototype is Available for Download
The Pokeit pre-flop prototype is available for download. You input the game state, your hole cards, and the action during the hand, and the Excel based tool gives you a 2-way equity estimate of your hand against each opponent’s hand range.
Hand range estimates are derived using a multinomial logit regression model. The general idea is that the model takes the input variables of game state and opponent action and then tells you the conditional probability that your opponent holds each of the 169 possible hands pre-flop. Each component of your opponent’s hand range distribution has an associated showdown equity value against your hand. To derive the estimated equity of your hand against the distribution, we multiply the probability of your opponent holding each hand, by the showdown equity, and sum the whole thing together.
The input variables of the model include:
♦ Player action on each pre-flop ‘round’ of betting (call/check or raise)
♦ Action behind the player (call, raise, 3-bet, etc.)
♦ A variable that combines position with # of players at the table
♦ Amount bet on each pre-flop ‘round’
♦ An interaction between player action and action behind
♦ An interaction between player action and position/# players
♦ An interaction between player action and amount bet
The data used to produce these estimates comes from a 181,007 hands worth of 6-max NL-Hold’em on PokerStars with limits ranging from $0.50-$1.00 NL to $3.00-$6.00 NL. The analysis is completely derived from the revealed hands of my friend Joe, who was kind enough to ship me his PokerTracker database. As you’ll notice when you test it out, Joe is pretty TAG. Some of his stats are vpip = 0.18, pf_raise = 0.12, wwsf = 0.43, and total_af = 2.77. Because the statistical model is based off of just one player, the prototype is somewhat impractical for in-game use. It should however give you an idea of what we have in store.
Just a few notes about the functionality of the Excel workbook:
♦ Top left of the ‘main’ sheet shows the position of each player at the table. It is here where you edit the player names, and create empty seats if <6 players. It is required that someone is named ‘hero’
♦ The gray cells throughout the workbook are your input cells. Variables with discrete values, such a hero’s position, hero’s hole cards, and player action, have pull down menus. Variables with continuous values, such as amount bet, require typing
♦ To input the action for the hand, first select one of 3 player action’s in the ‘action’ column: F – Fold, C – Call, R – Raise
♦ Next in the ‘total bet’ column, type in the total amount the player has bet up to that point in the hand. For example, if someone raises to $10 and you call in the BB, type in $10. If an opponent 3-bets and you 4-bet, type in the total value of your 4-bet
♦ Estimated 2-way equity is displayed in the ‘equity’ column. If the opponent has already acted in the hand, the conditional equity is shown. If action has yet to reach a player, equity against a random hand is displayed
♦ The ‘New Hand’ button resets the action
♦ The ‘equity’ tab, provides a graphical view of your hand’s equity against each 169 pre-flop hand categories. The generalized categories 1-13 of each hand are shown to the right, and you can highlight a particular category using the ‘category’ pull down menu
♦ Using the ‘view’ pull down menu, you can switch between viewing actual equity derived from ~50,000 Monte Carlo trials, the average equity of each generalized category, and a third view that shows the difference between the two
♦ Both worksheets have a table and chart combination which displays the hand range and category equities of each opponent. If ‘automatic’ is selected (cell J2 on the main sheet) its shows data for the player whose action it’s on
♦ The remaining worksheets house the innards of the model. Feel free to snoop around if you’d like
Download Pokeit Pre-Flop Model (3.70 MB) — Updated as of 4/07/10
- chaz